(1B) The product $(a+b)(c+d)$
Practice
Expand and simplify.
*Write your answers with powers of $x$ in descending order. $\left(\square x^2 \pm \square x \pm \square\right)$
$\left(x-1\right)\left(x-6\right)$
$\left(x+7\right)\left(x-6\right)$
$\left(x+8\right)\left(1+x\right)$
$\left(x+6\right)\left(6-x\right)$
$\left(-2+x\right)\left(x-3\right)$
$\left(4-x\right)\left(x+5\right)$
$\left(-2+x\right)\left(2+x\right)$
$\left(8+x\right)\left(5+x\right)$
$\left(4x+1\right)\left(5x-8\right)$
$\left(5x+7\right)\left(-3x+5\right)$
$\left(-7x+4\right)\left(-2+7x\right)$
$\left(x-4\right)\left(5+2x\right)$
$\left(7-x\right)\left(-x+1\right)$
$\left(-7+2x\right)\left(x-2\right)$
$\left(2-x\right)\left(1+6x\right)$
$\left(-1+5x\right)\left(2+3x\right)$